Just installed a new R7800. I am surprised to discover that it creates separate WiFi networks, one in the 2.4GHz band, the other in the 5GHz band. My previous wireless access point combined both bands under one SSID, and automatically selected the optimum frequency depending on the connected device

An 802.11 (Wi-Fi) router that uses the 2.4 GHz and 5 GHz frequency bands. Prior to 802.11n, dual-band routers handled 802.11a users in the 5 GHz band, while simultaneously supporting 802.11b and Why Choose Simultaneous Dual Band - Netgear Why Choose Simultaneous Dual Band? Dual Band Wireless Routers have the capability to transmit on the 5 GHz and 2.4 GHz wireless band. 2.4GHz though more widespread in usage (all 802.11b and g devices run on 2.4GHz only) has only 3 non-overlapping channels for transmission, which are crowded due to a lot of interfering devices- other Wi-Fi access points, microwave ovens, cordless phones How to Setup an Ultra Link AC1200 Smart Dual-Band WIFI Router Mar 07, 2019

The NETGEAR AC750 Dual Band WiFi Router delivers 300+433 Mbps† WiFi speeds, up to 3x faster than 802.11n. Simultaneous dual band reduces interference for reliable connections. The AC750 WiFi Router is compatible with current and future WiFi devices and backward compatible with 802.11n devices. External antennas improve WiFi signal strength for extended range and reliable connections

Belkin Official Support - Setting up the Belkin Dual-Band

Setup a Dual Band Router with Tomato Firmware

Belkin Official Support - Setting up the Belkin Dual-Band Ensure that your router is connected to the internet and that the SSID Broadcast feature of your router has been enabled. Take note of your Wi-Fi® name and password. If it's a dual-band router, make sure you have the Wi-Fi name and password of the two networks. Dual-router setup w/ a dedicated VPN Router: A step-by Oct 25, 2017